Assets not being served on Windows

Reported [here](https://groups.google.com/d/msg/play-framework/-bBABMl34ro/vsy6BQqBBcEJ) and [confirmed by another user](https://groups.google.com/d/msg/play-framework/-bBABMl34ro/YoVh5wpphJ8J).

> Has anyone experienced Assets controller issue after the upgrade? I couldn't retrieve assets (css, js, image) in public folder although it was working properly in 2.2.0-M2. The same problem happens to all the examples as well.
My dev environment is on Windows 7 + MinGW.